ThinkPad laptops include a proprietary interface called SMAPI BIOS(System Management Application Program Interface) which provides somehardware control functionality that is not accessible by other means.

This driver exposes some features of the SMAPI BIOS through a sysfsinterface. It is suitable for newer models, on which SMAPI is invokedthrough IO port writes. Older models use a different SMAPI interface;for those, try the "thinkpad" module.